I am wanting to know if applying ceramic tile to a concrete subfloor is appropriate. If so, should there be any type of vapour barrier placed first or not. I have not worked with tile before and would like to get it right. Project is a small bathroom - 38 sq ft. Also, what would be the best type of mud to use for good adhesion between the cement and tile, should I not require a vapour barrier. And lastly, after grouting, should the grout be sealed and if so what should I be looking for as far as product. Many thanks!

You can certainly install tile directly onto cured concrete. For preparation, you should make sure the concrete is clean and flat. The slab should be no more than 1/4" in 10' or 1/16" in one foot out of plane. Any current cracks should be addressed with an anti-fracture membrane. Covering the entire area to be tiled with an anti-fracture can reduce the chance that future cracks in the slab will transfer through the tile.

The only time you need a vapor barrier is if you have extreme hydrostatic pressure, although it certainly doesn't hurt to use an underlayment like Ditra to control moisture. And while Ditra isn't sold as an anti-fracture membrane, it would most likely keep moderate cracks in the slab from transferring through the tile. With only 38 sq. feet to be covered, Ditra would be a relatively small but wise investment.

Your choice of thinset is dependent on whether or not you use Ditra, but it's also completely dependent on what is available in your area. You should decide if you're going to use Ditra or another type of underlayment, or just an anti-fracture membrane, or simply bond directly to the slab, then you can decide what is the best thinset available to you. http://www.schluter.com/6_1_ditra.aspx



You should always seal grout after it's cured, particularly in an area that's difficult to clean like a bathroom. However, installing an epoxy grout can save you much cleaning time over the years to come. I've use Laticrete Spectralock a few times and it's very easy to work with. http://www.laticrete.com/architects/products/grouts/epoxy_grouts.aspx It's very stain resistant, and color consistent. While the cost is somewhat higher than standard grout, remember that you're doing a small area. The difference in cost between the two might be $50 or $60, but keep in mind that epoxy grout will not require sealing and will look good for years with minimal maintenance. Standard grout requires sealing every year or two, starts to look dirty after a few years, and has a tendency to vary in color and look splotchy if too much water is used during the cleanup.

Thanks so much for the info. You may be hearing from me again if something presents itself during the project.

Cheers!